Page 4 - Livestock and Companion Animals

30 • ANIMAL BIOLOGY AND TECHNOLOGY

is an animal without a backbone. Examples of invertebrates include shrimp, crawfish, hon-
eybees, spiders, mites, earthworms, and snails.
Vertebrates belong to the Phylum Chordata and to the Subphylum Verbrata. They have
many common characteristics. They have vertebrae (bones and cartilage) that surround the
nerve cord. Bones make up the internal skeleton that provides the body’s framework. Verte-
brates have a skull that protects the brain. They also have an axial skeleton made of the
backbone and skull. Paired limbs (arms and legs) are attached to the axial skeleton. Finally,
muscles provide movement by being attached to the skeleton.

CLASSES

Animals are in several classes. The three
main classes are birds (Aves), bony fish
(Osteichthyes), and mammals (Mammalia).
Snakes, shellfish, turtles, and alligators are
examples in other classes.

Birds

Some 9,000 species of birds have been
identified. Birds belong to the class Aves.
2–4. Birds, such as this Tucan, belong to the class Aves. The
Tucan is more like other birds than it is like mammals and fish. Birds can live in the air, on land, or in the
water. Most birds are wild; a few have been

C A R E E R P R O F I L E

ANIMAL TRAINER

An animal trainer works with animals to help them gain the desired skills to meet human needs.
Training varies with the kind of animal and the behavior that is desired. Horses are trained for riding.
Mules may be trained to pull a heavy load. Cattle are trained to lead in a show halter or to enter a stan-
chion.
Animal trainers need a good understanding
of the biology of the animals they are working
with. They need to understand the nature of the
animal and how it responds to human
demands. Animal trainers need to be patient
and always consider the well-being of an ani-
mal. Practical experience with animals is essen-
tial. Many animal trainers learn the trade under
the direction of an experienced trainer.
Jobs for animal trainers are found on farms
or ranches where animals are trained. This
photo shows a trainer working with a mule to
teach it a desired behavior. (Courtesy, Lucky
Three Ranch, Inc.)